Cummins ISC CM2150 (2007-09) Fault Code: 692 PID: 351 SPN: 1172 FMI: 4 Turbocharger 1 Compressor Inlet Temperature Sensor Circuit – Voltage Below Normal or Shorted to Low Source. Low signal voltage detected at the turbocharger compressor inlet air temperature sensor circuit.

Verify the electronic control module (ECM) calibration is correct. Check the calibration revision history found on QuickServe® Online for applicable fixes to the calibration stored in the ECM. If necessary, recalibrate the ECM.

An extension harness between the main engine harness and the turbocharger compressor inlet temperature sensor can be used, depending on the turbocharger arrangement.

On ISB with CM2150 engines, an extension harness between the main harness and the ambient air temperature/pressure sensor is always used.

Possible causes:

1)Signal circuit shorted to ground in the harness
2)Signal circuit shorted to return or ground in the sensor
3)Damaged sensor.

Possible repairs:

1)Replace the turbocharger compressor inlet air temperature sensor.
2)Replace the ECM.
3)Repair or replace the engine harness.
4) The removal and installation of the connector may correct the problem.